Surfactant-assisted etching in biomimetic mineralization of ferric phosphate

A solution-based etching process often takes place in remodeling natural minerals and building natural wonders such as stalactites and stalagmites. Enlightened by this spontaneous mineralization process, we proposed a surfactant-assisted etching in biomimetic mineralization aiming at a better imitation of natural environments for constructing complex and extraordinary architectures of ferric phosphate. The mineralization process is achieved by thermally aging soluble ferric and phosphate salts with the existence of cetyltrimethylammonium bromide (CTAB) as surfactant. Based on the experimental evidence, the generation of such architectures relies on the competition between acidity-induced etching and selective protection by surfactant adsorption. This novel structure represents a new member with a hollow interior in the family of various micro/nanostructures and indicates that materials with attractive patterns can be readily achieved through this strategy.